[Mi5tahclean]

Greetings,

I'm a chef located in the Philippines and I am planning to make century eggs.

Now my worry is lye. Lye can be very very toxic, and I am wondering can I replace it with baking soda. If so, how much? If I use the one that you can get in the hardware, should I adjust amount?

So that you would know my predicament, I will attach the address for you to look.
http://bizfil.com/different-methods-of-making-century-egg/

Many many thanks in advance.

[Arkcon]

Well, briefly, the recipe isn't authentic if you don't use the correct ingredients. That's a little trite, I know, but still true enough to mention.  No, baking soda (sodium bicarbonate) is likely not basic enough to produce the chemical changes needed.  Washing soda (sodium carbonate) might work better, but it will be difficult for you to find food grade washing soda and not -- well, washing grade washing soda.

[billnotgatez]

@Mi5tahclean
Have you read the WIKI on this topic
https://en.wikipedia.org/wiki/Century_egg

[Mi5tahclean]

How about lye? I know there is such a thing as food grade lye and other lye used in industrial usage, can industrial lye work?

[Mi5tahclean]

P.s. yes I read it billnotgatez but again, there are problems in procuring those chemicals here. How about lye water? It's quite common here.

[Corribus]

How about lye? I know there is such a thing as food grade lye and other lye used in industrial usage, can industrial lye work?

Food grade chemicals are food grade for a reason. You can use industrial chemicals if you fancy heavy metals, residual solvents, and so forth in your meals, of course.

[Mi5tahclean]

Can liquid lye work?

[sophotect]

I'm really worried that you seem more interested in making the eggs than understanding the science.

There is only one kind of sodium hydroxide (lye).

Food grade means that the lye is pure enough to be used in food.

If the lye you can obtain is not food grade, do not use it to prepare food, period.

[Borek]

There is only one kind of sodium hydroxide (lye).

Not necessarily. This is the most common use of the name today, but in the past it could mean anything strongly alkaline. Depending on how old the recipe is, it can call for NaOH or something else.

Besides, I am almost sure I have seen century eggs recipes calling for the use of lime, not lye, so it is not exact compound that matters, but the fact that it is a strong base.

[Mi5tahclean]

I think I need to clarify some things:

1) there is a liquid lye here used in cooking which is called "lihia". It is used for rice cakes to cleaning of pig's guts.

2) the recipe I attached in one of my previous posts has three kinds of recipes.

I hope this helps.

And yes I am very much into wanting to make these eggs as they are a very tasty food items and I want to provide healthy century eggs without heavy metals.

[sophotect]

Not necessarily. This is the most common use of the name today, but in the past it could mean anything strongly alkaline. Depending on how old the recipe is, it can call for NaOH or something else.

True. There is also potassium hydroxide, which may be easier to obtain in some parts of the world. Calcium hydroxide, which is possibly even more dangerous. But the historical uses of the word 'lye' seem less important than the current intended application.

I assume, perhaps unreasonably, a chef is making century eggs for human or animal consumption.

If this is not true, then the question becomes process oriented - what materials & methods will achieve the desired result? The wiki has both an answer and a concise explanation of the chemistry: https://en.wikipedia.org/wiki/Century_egg#Modern

If it is true, then I am curious as to why we are helping Mi5tahclean prepare food with substandard ingredients? The question needs more elaboration.

[curiouscat]

Calcium hydroxide, which is possibly even more dangerous.

Why do you think Ca(OH)2 is more dangerous?

[sophotect]

Why do you think Ca(OH)2 is more dangerous?

Because it is a fine powder & could be blown into the air. I know because I have some right now. I've touched it with my fingers with no ill effects but I wouldn't want it in my eyes. OTOH, I have had aqueous lye dripped on my hand which caused a permanent scar, but there was no danger to bystanders because it was (originally) the bead form.

[Borek]

Are you sure you are not mistaking CaO with Ca(OH)₂?

[sophotect]

I had to go check. Yes, I was confusing CaO with Ca(OH)2.

All these wasted years of unnecessary caution! Wow, guys, thanks!